Unfortunately, I was so ga-ga over how beautiful the framing was, I didn't notice that I wasn't very sharply focused--on either Moon or trees (although they should be effectively identical focus). This is a prime focus at ASA 100 with the 17.5" f/4.5 reflector, 1/90th of a second.
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I also tried to do eyepiece projection on Jupiter--still having a heck of a time getting a decent focus. You can tell that the cloud bands are there. Being still low in the sky, and with the Moon washing everything out, the cloud bands weren't dramatically more crisp in the eyepiece. This was 1/20th of a second, ASA 400, with an 18mm orthoscopic eyepiece projection.
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I have also decided that whatever the limitations of Big Bertha's mirror, it is not clear that it has a turned edge. I am beginning to think that the problem was the lack of support of Big Bertha 1.0. I took the mirror mask off last night, and I couldn't see that there was any decline in image quality. I also tried to do the star test on Antares. While I couldn't get the diffraction rings (Antares was low in the sky, and there was a bit of turbulence), I didn't see any of the outside focus symptoms of turned down edge. It may not be a great mirror, but I can feel comfortable using the full aperture of the mirror now.
The big problem is that I need to get the telescope back down to Earth! I have the mount sitting on a 10.5" plus 12" column right now to get it high enough off the ground board to avoid collisions. What I need to do is is take out the 10.5" column, and build appropriate hardware to bolt the 12" column to the ground board. I still need a better stepladder than I am using, but even taking 10.5" out of the elevation would make a world of difference.
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